Molecular characterization of the wild relatives of safflower (Carthamus tinctorius L.) in Turkey as revealed by ISSRs

In the present study, we used 39 plant samples representing six Carthamus taxa collected from different regions of Turkey: 11 of C. dentatus, 5 of C. glaucus, 18 of C. lanatus, 3 of C. persicus, 1 of C. tenuis subsp. tenuis and 1 of C. tenuis subsp. gracillimus. On these samples, we screened nine ISSR markers for polymorphic products. We generated 151 polymorphic bands. In a dendrogram based on these ISSR bands, the first branch was C. tenuis subsp. gracillimus, then C. persicus formed the second group. The rest of the taxa were grouped in two clusters: the first included C. lanatus, C. tenuis subsp. tenuis and C. glaucus, and the second included C. dentatus. Within the first cluster, C. tenuis subsp. tenuis and C. glaucus grouped together and then united to C. lanatus. Representatives of the same taxa consistently clustered together. Also within species, the groupings were generally concordant with their geographical distributions.     

Spatio-temporal variability of drought characteristics across Pakistan

Climate change in Pakistan has a great impact on the spatial and temporal variation of precipitation and ultimately alters the frequency and duration of droughts. In this study, spatial and temporal trend analyses of precipitation and droughts were observed at 58 meteorological stations across Pakistan from 1981 to 2018. The existing trend analysis methods were evaluated to address the issue of serial correlation in the climatic data. Results of precipitation analysis showed significant decreasing trends in winter (November, December) and significant increasing trends were observed in summer (June and September) at a confidence level of 95 percent. The magnitude of the precipitation trends showed the highest variation during summer season and the least variation in winter season. Rotated Principal Component (RPC) analysis showed the severe droughts (high positive loading) in southeastern side (Sindh province) of Pakistan due to lack of summer rains. Furthermore, variance correction approaches are identified as the most suitable in coping with the effect of serial correlation. The highest drought frequencies were observed in the southern areas of Pakistan and the drought events are expected to occur more frequently in the late winter, early spring, and early autumn, while droughts were expected to occur least frequently in summer.

     

The Effect of Salicylic Acid On Photosynthetic Characteristics,Growth Attributes,and Some Antioxidant Enzymes On Parsley (Petroselinum crispum L.) Under Salinity Stress

Gesunde Pflanzen - Parsley (Petroselinum crispum L.) is widely used in food, medicine, cosmetics, and pharmaceutical industries. This research was conducted to determine the effect of six...     

Binding,fractionation, and distribution of Cs,Co, and Sr in a US coastal soil under saturated and field capacity moisture regimes

Purpose

The concerns of the public on safe handling of nuclear energy power facilities have increased due to the recent nuclear plant accidents in Japan and others. Cesium, cobalt, and strontium are a few of the major radionuclides released from nuclear power plant accidents. The objectives of this study are to investigate binding, distribution, fractionation, and transformation of cesium (Cs), cobalt (Co), and strontium (Sr) in a US coastal soil under saturated paste (SP) and field capacity (FC) moisture regimes.

Materials and methods

There are four major nuclear power plants in the coast region around the northern Gulf of Mexico where coastal soil often undergoes soil moisture change. A coastal soil was taken from the middle region of these major nuclear power plants and spiked with different concentrations of cesium, cobalt, and strontium salts. The sequential selective dissolution technique was used to investigate the transformation and fractionations of these metals in the coastal soils affected by moisture regime, a key factor in the coastal environment.

Results and discussion

The adsorption kinetics showed that both Co and Sr reached the adsorption plateau even after 5 h of adsorption, indicating a fast initial adsorption process in the coastal soil. Cesium, cobalt, and strontium were dominantly presented in the soluble and exchangeable form (EXC) (Cs?>?Co and Sr), which linearly increased with the addition levels, possessing the high bioavailability, mobility, and ecotoxicity. Saturated regime significantly reduced the soluble and exchangeable form compared to field capacity moisture regime.

Conclusions

The current study provides the fundamental understanding for designing the cost-effective remediation technology to remediate these metals in coastal soil by targeting on the soluble and exchangeable forms and better prepare the USA for future potentially nuclear power plant accidents.

     

Evaluating and Modeling of the Seedling Growth Ability of Wheat Seeds as Affected by Shallow-Saline Groundwater Conditions

The adverse effects of shallow-saline groundwater may vary among crucial growth stages of crops by decreasing crop growth and productivity. The present study aimed to assess the germination and seedling growth ability of wheat seeds grown in four different (0.38, 2.0, 4.0, and 8.0 dSm^?1) groundwater salinities (GWS) and three (30, 55, and 80?cm) groundwater depths (GWD) condition. To achieve this aim, wheat crops were grown in drainable lysimeters under rain shelter conditions until the maturity stage, and then wheat seeds were harvested from various saline groundwater conditions. Afterward, wheat seeds were germinated to identify the performance of germination and seedling growth attributes. Response surface methodology (RSM) was used to determine the optimal growing wheat seeds condition, which had high early seedling growth performance. The results showed that the seedling growth performance of wheat seeds increased with increasing GWDs, while decreased with increasing GWSs. Based on the RSM findings, we suggest that GWD and GWS should be at least 42?cm and at most 5.46 dSm^?1, respectively, for sustainable higher wheat yield and seed quality. Finally, this study could provide considerable information for selecting strong and healthy wheat seeds grown under shallow saline groundwater conditions.

     

Grain Yield Mapping: Yield Sensing,Yield Reconstruction,and Errors

Research findings are reviewed focusing on yield sensing methods, yield reconstruction, mapping, and errors. Yield sensing methods were explained and yield mapping process was briefly introduced. Grain flow through different combines was explained and the effects of combine dynamics on yield measurement accuracy were discussed. Other errors caused by various sensors that are utilized by a yield monitor were included. It was concluded that with proper installation, calibration, and operation of yield monitors, sufficient accuracy can be achieved in yield measurements to make site-specific decisions. Nevertheless, attention must be paid when interpreting yield maps since yield measurement accuracy can vary depending upon the measurement principle, combine grain flow model, size of management area chosen, and the operator's capabilities and carefulness in following instructions to obtain the best accuracy possible under varying field operating conditions. Some of the errors can be filtered out by careful analysis of the raw yield (or flow rate) data provided by yield monitors. Researchers have focused on crop flow models to improve yield reconstruction process. A yield reconstruction algorithm that effectively handles non-linear combine dynamics has not been developed by researchers yet. More efforts towards yield reconstruction should be encouraged.     

Growth stage-based response of wheat (Triticum aestivum L.) to kinetin under water-deficit environment: pigments and gas exchange attributes

Plant growth regulator, kinetin, is known to modulate the key physiological processes under abiotic stresses in different crops. However, kinetin-mediated response at different growth stages of crop plants is lagging behind. Therefore, a field experiment was conducted to appraise the potential role of exogenously applied kinetin in alleviating the effects of water scarcity on wheat. Three levels of kinetin (0, 75, and 150 mg/L) were used either as seed treatment or foliar spray at the vegetative or the post-anthesis stage. Water deficit markedly reduced shoot fresh mass, plant chlorophyll level, flag leaf photosynthesis, stomatal conductance, and transpiration rate. Degradation of chlorophyll a was greater in plants subjected to post-anthesis water-deficit conditions. However, plants growing under continuous water-deficit conditions had significantly lower concentration of chlorophyll b than those treated with water scarcity at the post-anthesis stage or receiving normal irrigation. Inhibited photosynthesis of wheat in response to post-anthesis water-deficit conditions was largely due to non-stomatal factors. In contrast, stomatal factors were the main constraints for photosynthesis in plants growing under continuous scarcity of water. Plants subjected to continuous water starvation had markedly lower grain yield than those subjected to water-deficit conditions at post-anthesis stage. Application of kinetin before seed sowing or at the post-anthesis stage significantly reduced the negative effects of drought on flag leaf chlorophyll and stomatal conductance. Lower level of kinetin (75 mg/L) was found to be more effective in mitigating the inhibitory effects of water shortage on photosynthesis and growth, and improved grain yield under water scarcity.     

Assessment of variation in drought tolerance using some key physiological criteria in potential wheat (Triticum aestivum L.) cultivars of different geographic origins

The present experiment comprised seven wheat cultivars, two drought levels (0 and 17% PEG-8000) and four replicates. The seeds of six wheat cultivars (Al-lugaimi, Bonus, Kronos, Yecora-rojo, Irena and Sama) were supplied by the King Saud University, Riyaz, Saudi Arabia, whereas S-24 was obtained from the Department of Botany, University of Agriculture, Faisalabad. The seeds were allowed to germinate and grow for 20 days in medium having full-strength Hoagland's nutrient solution or Hoagland's solution with 17% PEG-8000. For the appraisal of drought tolerance, various physiological traits such as gas-exchange attributes (A, E, C_i, g_s , and A/E), leaf water relations (ψ_w, ψ_s and ψ_p) and the activities of key antioxidant enzymes (SOD, POD and CAT) were determined. On the basis of biomass and gas-exchange attributes (A, E, and g_s ), cultivars Al-lugaimi and Sama were found to be drought tolerant, cultivars Yecora-rojo and Irena moderately drought tolerant, and cultivars S-24, Bonus and Kronos drought sensitive. However, plant osmotic adjustment and the activities of potential antioxidant enzymes (SOD, POD and CAT) were not found to be associated with drought tolerance of the different wheat cultivars.     

Morphological and molecular evaluation of Turkish rice (Oryza sativa L.) landraces

Genetic Resources and Crop Evolution - This study was carried out to evaluate Turkish rice landraces, in 2016 and 2017. Twenty-nine morphological traits were used for morphological evolution and 10...     

Physiological effects of psyllid (Paratrioza cockerelli) on potato

Feeding by psyllid nymphs causes “Psyllid yellows,” a characteristic yellowing of shoots which results in a dramatic loss of tuber yield. If psyllid infestation is not controlled, the onset of shoot yellowing and growth reductions can occur within two weeks. When insecticides are applied after yellowing, recovery of plants often is not complete. In this study comparisons were made of the physiology and growth of tops and tubers of recovered and permanently injured potatoes of the cultivars ‘Denali,’ ‘Kennebec,’ and ‘Norgold Russet.’ Permanently injured plants senesced rapidly, developed less shoot growth, aerial tubers and shortened and thickened internodes. They had lower tuber yields than plants that recovered. Permanently injured ‘Denali’ developed shoots on old flowering stems. In permanently injured plants of all cultivars, the tubers were small and badly misshapen but numbers increased. In recovered ‘Kennebec’ plants tubers were also misshapen, but were of average size. Tubers of recovered ‘Denali’ and ‘Norgold Russet’ were of acceptable shape. In samplings made during tuber growth, dry weight percentages of total soluble sugars, sucrose and glucose of tubers from permanently injured plants were found to be the same as those of recovered plants. In all cultivars, starch percentages of tubers from permanently injured plants were higher than that of the recovered, but the pattern of carbohydrate content changes was similar for permanently injured and recovered cultivars.